Background and purpose: Nonalcoholic fatty liver disease is one of the most common causes of chronic liver disease and is a major public health problem worldwide. In recent years, the prevalence of nonalcoholic fatty liver disease has increased in children and adolescents. This study aimed to investigate the effect of silymarin on children with nonalcoholic fatty liver disease.

Materials and methods: In this randomized crossover clinical trial, 40 children with nonalcoholic fatty liver disease were divided into two period treatment groups. Patients in group A received 140 mg silymarin capsules, three times a day in the first three months, and after one-month washout period they received placebo for three months. Group B received placebo at first and then silymarin. Liver enzymes, LDL, HDL and triglyceride levels were measured at baseline and after the first and second stages. At the end of three months, the patients underwent ultrasonography.

Results: The study included 36 boys and 4 girls. After treatment with silymarin no significant changes were seen in weight, AST, ALT, HDL, LDL and TG levels of patients compared with those of the control group (P>0.05). However, fatty liver grade decreased significantly after treatment with silymarin (P=0.02).

Conclusion: As previous studies on adults, our results showed beneficial effects of silymarin on reducing fatty liver grade in children with nonalcoholic fatty liver disease. Larger studies with longer treatment periods are recommended in order to achieve comprehensive results.

(Clinical Trials Registry Number: IRCT2015012520781N1)